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Feb. l2, 1929.

A. O. HOEFTMANN HIGH TENSION CABLE Filed April 9, 1927 Inventor:

{X4/VDE@ 0. Hoff TMH/v/v,

Patented Feb. 12, 1929.

unirnnjsraras PATENT orriea.

`ALriinnjEn o.,nolnirrirmrnv,v QE':WORCESTERMAssACHUsETTs, AssreNoR fro THE y JERSEY.v

i "particularly to :highftension eablesh'aving -a 'relatively heavy lbody, of'impregnated"in' sulating Iiiate'riala surrounding thefconductoi", 'andhas for its object thep'r'ovision of a'hvell cable eii'striletion 'invvhieli the virnprgnat'ing insulatingcompound '1nay"beread;ily"fo` ed through" lthe "condufctg'ir'cv t'o iinpregnate @the body'- offnfe insulating interim# f e Heretofore hollow eoreistrande'd cables ,have -beenrnadeflorthigh tnsin A'Iiiese cables have consisted? of a" hollow icoi-eeom'- poised'o'f 'af spiraltor other operil and :flexible core',y over Whieh'are laidith'evrquir'ed number of solid wires necessary to inake'upthe Iconductor of given capacity.' The conductor thus" forined is tlien' insulated" bywrapping a heavy body of insulating paperoflit Vand Athen' 'impreguat-il'ig'; the' paper "an insulating -'c'onipound: EThe"insulatingg compound 'is forced from the "external part; of the p'aper vinsulation through the l cable into the' hollow fcorei'or vice 'versa-:roin the eorethrough lthev cable and 'insulating papergff i VhenftheI'conductor is prfectlylaid up and moreespecially; when thre'are'; several layers 'of'wiresv around the 'teorial each llayer being laid upiirthe"ppsitedirection, it is diiicult and sone cases practically impossible to force theinsulating 'cbmpound throu'ghithe vconductor and therefore, imperfect insulation-resulten; i The 'presentiiiventibn :overcomes the above difiieulties and :provides f a' cable in which the `conductor is soformed-that the 'insulating compound may be "readilyf forced therethrough. 4' i Y Figure 1 is a plan view of a short length of cableeonstrueted in accordance with this invention and broken away "to Show each of the elements in plan.

Figure 2 is a transverse section through the cable shown in F igure 1.

Referring more particularly to the drawings, the nume-ral 2 designates the hollow core 0f the cable shown as comprising a relatively heavy Wire formed up Spirally. An inner layer A of Wire elements is laid up spirally around the core 2 and an outer layer- B of Wire elements is laid up spirally in the opposite direction around the layer A to complete the conductor of the cable.

ERIGAN STEEL AND wiRE CoMlANY 0E NEW JERSEY, A ooEroRA'rIoN o E NEW I i HIGH-TENSION CABLE..vvv

ppnc'ai'aiefanie, 1927. seriarno. 182,419.

Eaohof the `layers A and B of wire elements' are composed of a plurality ot relatively; hea'vysiiigle or solid wire elements Band a`plurality of multiple Wire elements 4., The elements 4 are composed vof three rlt'ivlyfliglit'gage wires laid up or twisted together spirally. The velements 3 and 4'are of substantially-the same diameter and of it equal eap'eity `t y v l-I 'have sllowir'evei'y ythird wire element 'o feachwftlie"layers A and B consisting of the multiple lWirerelements 4. Itl will be riniderstood, however, that this arrangement may be varied and either a greater or fewer number of the elements 4 may be used, also that 1f desired7 the elements 4 may be omitted entirely from either, ofthe layers A or B,

"Ahe'avyljbody of paper insulation G is formed around Vthe cable conductor and is -eon1plolsedtf()ifapluralit "of layers 'of paper strips ivrapped spirally, with the spirals ot' one layer` overlapping the joints of the next leen. 'f Alead Ysheath or covering 7 is provided overjthe paper insulation 6: after the insulation` 16 has been impregnated. V,'lh'e VinterstieesA of the stranded Wire elements 4 s'ervetol form openings throughout thev onductorportion of thecable to permit the ready'passage of the insulating compoundninltoptor from' the paper insulation and, therefforzj'l greatly facilitate the operatin 'impregnating the'/ paper G.

"It is sometimes' necessaryt-o first .satrrate the paper insulation G'Witha light oily compoundfand' then to use a still heavier conip'ound'forfinsulating nent'Y to the outer surface ofthe conductor portion of the cable, and in 'such 'eases it is essential to have the ifonductorfporous or provided with openings to'ipernii't such compound to paus therethrough.

A cable having its conductor portion formed as described above may have its insulation 6 impregnated lnore thoroughly and in materially less time than cables constructed Without the stranded wire elements 4.

While I have shown and described one specific embodiment of my invention it will be understood that I do not wish to be limited thereto sinee various modifications may be made Without departing from the scope together.

ol iny invention as defined in the appended and the other of said elements comprising clainis. As forvinstanoenit .b e understrands Composed o' a-plurality of relatively stood that -.a".`-.siiigle Wire ff-reotangular, liglitgag `Wires laid upspirally. triangular or other polygonal erosssection 6, A stranded high tension caole Comprisand twisted to form spiral grooves in its ing z i hol low core, a plurality offlayerslof surface iria'yhe"substitutedfor'theiriiultiple Wirfelnlt "l'iiiilp 'Spifzllyaroiiiidsaid Wire eleine`n`ts'vfl1f-A '55 71 f eore, at leaston'eof saidllaye'rsqf ele- I claiml in ents being composed of soniei'elatively 60 1. A stranded high tension cablem'pris'l'Y 'heavy ugage single Wire elements and some ing a core, a plurality o ,yvireelements-laid felelients1x op Imposed of a plurality of relaup spirally around said ore, the major portively lig 1t gage v{vires laid up Spirally. tion of said vvireelementseqnsisting oflrela- .7, A stranded high tensioncableeon 1pristively'. heavygage singleayiresand .theother ing ahollow corefrav plurality ofrflayers .of 65 of saidelementslpeingompgsed oa plural,- .Wireelementslad up. vspirally aroundilsaid ity O-I'MQHTJQWfrBeht gaieani" .Stranded .Gwent-kasten@-Of Saidflayers-oilwireele- 2. A stranded'.higlitension-,ableomprisheavy-, gagefsingle Wire...elementsand some inga hollovneoe, apliirality fLWireQele- :elementsiceinposed o'fga l.plurality -ofgrela'- 7o ments laidupspirally aroiiridgsaadooreythe .tively .lightlgagewires laid up spirally, and

major-'portion of said Wire eleiiientsonsistall of said elements beingqo substantially7 ingo relatiyelyheavygagesingle Wires and the .same diameter. i l, the other o fsaidge ementslorinpiiisng,strands 8'. ;-A stranded Yhigh tension eable compriscoinposedfof .plurality',o;f.}}elati}ely light hollow gooie, a plurality of ,layer'sof 75 gage wires laidiiiq A s p ii-al l'y, and a .relatiyely .Ivi/ ire elements laidup. spirally around-said heavyjliody offinsulatging materialsurround; core, saidlayeits 'of wire elements each being sistinglgv of relati ing Said Wil-e'jelsygtg i .eoinposed of some relatively lieavyfsingle :n 3. 'A strandedhiglrtensipn eahl e o mpris- .p'ii'eelements andl otherl elements .composed mg a ..11eiiqw; or@2...a..p.1ui;a1ityf; efrfxyue: ele- @fe rlerahfy 0i felatlvely light gage Wires so ments, laid up. `spirally arguiidgsaid orelfthe laid upspirally. i maar porci@ ma@"immanentei a A .scfz'mdd high tens-wn,cabiecpmpiis.-

. velyilaaiggeielealerir -legfelwllwwea=i 1uely0alayerlof and the thr'fQadeleineiitaeorilprising Wire elexnents ,laid up. spirallyaroundsaid strands composed'Qi.aqliiialitygofrelatively Qie', 1said layers of vire elements each; being S5 light gaglewires laidiu'pspirally, and 'alrelaeonip'sedof .someY relatively 'h eavy single tively heavybodyof impregnated paper in'- 'Wire elenien'ts andotherelements composed `d Q e, le' r:i`ientsf. O f a ;plural i ty..of relatively lightfgagelwires 4. A s'traiidedlhighptensaon ahleeomprls.- laidu p. sp1rall y,' and a heavy body.. o f 1ining a hollovfzfe' y Qffwire'elefp'regnating paper insulation surrounding the 90 nientslaiduppirally arou d` said "oor e,fthe outer-layeigof.saideleinents a major portionfofrsa" fr eeleiiieritsfonsis't- IOJAstrandedlhigh tensionffahleg.corrijing of relatiyl hfeayj gagesinglegwires p i'isinga hollowpermeablecore, a plurality fw: and the other:l of v sali/d(lenients'comprising olayeis of l#ri-re .elementsflaid .up 4,sph-ally strandseoinposedofthree relatiyely vlight around said core, :1 body of impregnated 95 gage ivireslaidfup'tspir y 'aiidla relatively vinsulating v material surrounding the. outer heavy hody o f yin s'i i l a' t`1 1'ig 'Iiiaterial surroundlayer of said Wire elements, andsome-of said lif'wMH-,g- 5. A strandedlii'ifli tension.fcahlelcompris Vsaidlayers of wi re elements being of polygiiig a hollow. 'eor'e ,fa' pluralityowire ele onal cross-section and having theirsurlfaces 100 nients laid up fairoli'ndsaid Core, all provided with spiral grooves. 'o fs'aid elenieiits/being'olsiihstanfially the In witness whereof, l. have ,hereunto saine dian1ete.i,`some 0.'sai d.elnientseon signed my naine sist-ing' of relatively heavy gage, Single wires ALEXANDER O. HQEFTMANN. 

